The ultimate goal of the Program Project is to improve an existing infrastructure (scientific, medical, and technical) which supports coordinated multifocused, multidisciplinary development of magnetic resonance imaging (MRI) used for the guidance of interventional and surgical procedures in some well-defined clinical areas. The proposal consists of five thoroughly interrelated projects. Project 1 is designed to develop MRI-based systems and techniques for intraoperative control of thermal treatment of tissue. The target tissue will be treated with a variety of modalities including interstitial laser therapy, cryotherapy and high intensity focused ultrasound surgery. The project will address the central problem in thermal surgery, which is intraoperative control of the tissue damage. This investigation will extract the maximum amount of information from the intraoperative MR images and develop visual feedback and automated control systems for image-guided thermal ablations. Project 2 will test the hypothesis that high intensity focused ultrasound surgery guided and monitored by MRI is an accurate and safe method for noninvasive tissue coagulation. The Project includes clinical feasibility testing of breast tumor treatments. Project 3 will develop and implement high performance computer integration of preoperative MRI and CT data with intraoperative images in order to guide surgery. To accomplish this goal, the investigators will consolidate existing high performance computational hardware, networking facilities and image processing software into a system which can provide online information to surgeons during the execution of operative procedures. Project 4 will develop novel MRI encoding methods. The investigators will implement and improve the so called adaptive imaging techniques and optimize the information-gathering capability of the prototype open configuration MR therapy (MRT) scanner.